STL file of a hand basin for 3D print

I’m looking to make this basic sketchup model of a hand basin into an stl file ready for 3D printing. The issue that I have is that the model isn’t solid, I would like to add a 5mm radius to the edges and a slight dip in the centre of the water run. The dimensions are 340mm diameter with a 32mm hole and basin bottom depth 35mm for a for Click Clack Basin Waste like this: https://www.victorianplumbing.co.uk/moon-slotted-click-clack-basin-waste-chrome-mbw01
Attached is a screenshot of the stl file, dwg file, basin waste image and CGI image which I can provide.